1. Field of the Invention
The present invention generally relates to a right angle type connector used for balanced transmission of data signals, and more particularly to a right angle type connector which is used for balanced transmission of data signals having its connection part protruding from a window of an electronic device and its rear part housed inside the electronic device mounted on an end of a printed board in a state of being mounted on an end of a printed board.
2. Description of the Related Art
As for types of data transmission, there is an unbalanced transmission type of transmitting data signals by using a single electric wire for each corresponding data signal. Another type of data transmission is a balanced transmission type (differential transmission) using a pair of electric wires for each corresponding data signal. In the balanced transmission type, a positive signal and a negative signal with a size equal to but with an orientation opposite to the positive signal are transmitted simultaneously. The balanced transmission type has an advantage of being more resistant to noise compared to the unbalanced transmission type.
Accordingly, the use of the balanced transmission type is increasing for data signal transmission among electronic devices such as computers, servers, switchboards, and routers. In such a case where the balanced transmission type is used, the electronic devices are each provided with a balanced transmission connector(s), and the electronic devices are connected to each other by connecting balanced transmission connectors of the ends of a balanced transmission cable to the corresponding balanced transmission connectors of the electronic devices.
In recent years and continuing, the speed of transmitting network data signals is increasing along with the increase of information processing speed. As the signal transmission speed increases, electromagnetic noise more easily emanates (leaks) from the location at which the connector is situated. In order to prevent such leakage, it is important to strengthen the protection against electromagnetic noise and take appropriate measures against EMI (Electro-Magnetic Interference).
FIG. 1 shows a conventional example of a connector 10 (See for example, Japanese Laid-Open Patent Application No. 10-261457). The connector 10 is a right angle type connector used for balanced transmission of data signals. The connector 10 includes a connector main body 13 having a contact member 12 assembled with an electric insulating block member 11. The connector main body 13 is reinforced by being housed in a housing 14.
The connector 10 is mounted on an end part of a printed board 20 in the manner shown in FIG. 2. In FIG. 2, the connector 10 is fixed to the printed board 20 by having leg parts 14a of the housing 14 inserted in the holes 21 of the printed board 20. This inserted portion is soldered, to thereby secure the fixed state. A connecting part 15 is provided on a front side of the connector 10 in a manner protruding from a window of a panel 31 of an electronic device 30. The connector 10 is connected to a cable 40 used for balanced transmission by engaging the connecting part 15 with a connector 41 provided on an end part of the cable 40.
When viewing a rear part of the connector 10 (i.e. the part of the connector 10 situated toward the inside of the electronic device 30), a portion 12b of the contact member 12 is in an exposed state. The exposed portion 12b of the contact member 12 causes electromagnetic noise 50 to be irradiated inside the electronic device 30. Accordingly, an electronic component(s) 51 situated inside the electronic device 30 is susceptible to adverse effects from the electromagnetic noise 50.